magicjc

iTrader: (3)

The battery in my FD drains over night after charging so that I can't even start the car. I purchased a multimeter to find out what's causing the parasitic draw. I don't know the age of the battery, which is a Optima Yellowtop. The battery has discharged a few times because I forgot to turn off my boost controller.

The instruction manual that came with the multimeter instructs me to switch the multimeter dial to the "10A (or 200 mA)" position. When I test the current draw, the display shows 0.20. Is that too much power being drawn with all accessories off?

I pulled all the fuses and found that my GReddy Profec-B and Defi Link ECU is drawing about 0.8 and the 10A "Room" fuse (according the Mazda Service Manual) is drawing about 0.1. When both fuses are pulled, I get about .02.

So are those numbers high? I google'd looking for some tutorial to understand the numbers but I can't figure it out. How much is 0.20 when the dial on the multimeter is at 10A.

The manual says typical current draw is about 100mA. Is the draw normal or my battery just bad?

rexman13b

iTrader: (7)

.20 is 200 milliamps which is too much. specs for most vehicles is no more than 50 milliamps which is 0.050 also when you hooked up the meter did you let the car sit for awhile so all the on board modules went back into sleep mode, some cars take as much as 20-40 minutes to power down. as far as hooking up the meter setting on 10A put the read lead into the amps port on your meter and black is common. i always check on the negative side of the battery. black lead touching the negative post and the red lead attaches to the negative battery cable. then it will probably jump up to a couple amps for a little while so the modules capacitors get recharged then after a while it should level out to the actual reading. if you do have a draw, the only way to find is to start pulling fuses while watching the meter until you narrow it down to the right circuit. it would also help to have wiring diagrams to look at.